/*

 * Licensed to the Apache Software Foundation (ASF) under one

 * or more contributor license agreements.  See the NOTICE file

 * distributed with this work for additional information

 * regarding copyright ownership.  The ASF licenses this file

 * to you under the Apache License, Version 2.0 (the

 * "License"); you may not use this file except in compliance

 * with the License.  You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

package com.bff.gaia.unified.sdk.io.solr;



import com.google.auto.service.AutoService;

import com.bff.gaia.unified.sdk.coders.*;

import com.bff.gaia.unified.sdk.util.VarInt;

import com.bff.gaia.unified.sdk.values.TypeDescriptor;

import org.apache.commons.compress.utils.BoundedInputStream;

import com.bff.gaia.unified.sdk.coders.AtomicCoder;

import com.bff.gaia.unified.sdk.coders.Coder;

import com.bff.gaia.unified.sdk.coders.CoderException;

import com.bff.gaia.unified.sdk.coders.CoderProvider;

import com.bff.gaia.unified.sdk.coders.CoderProviderRegistrar;

import com.bff.gaia.unified.sdk.coders.CoderProviders;

import org.apache.solr.common.SolrDocument;

import org.apache.solr.common.SolrInputDocument;

import org.apache.solr.common.util.JavaBinCodec;



import java.io.*;

import java.util.Arrays;

import java.util.List;



/** A {@link Coder} that encodes using {@link JavaBinCodec}. */

class JavaBinCodecCoder<T> extends AtomicCoder<T> {

  private final Class<T> clazz;



  private JavaBinCodecCoder(Class<T> clazz) {

    this.clazz = clazz;

  }



  public static <T> JavaBinCodecCoder<T> of(Class<T> clazz) {

    return new JavaBinCodecCoder<>(clazz);

  }



  @Override

  public void encode(T value, OutputStream outStream) throws IOException {

    if (value == null) {

      throw new CoderException("cannot encode a null SolrDocument");

    }



    ByteArrayOutputStream baos = new ByteArrayOutputStream();

    JavaBinCodec codec = new JavaBinCodec();

    codec.marshal(value, baos);



    byte[] bytes = baos.toByteArray();

    VarInt.encode(bytes.length, outStream);

    outStream.write(bytes);

  }



  @Override

  public T decode(InputStream inStream) throws IOException {

    DataInputStream in = new DataInputStream(inStream);



    int len = VarInt.decodeInt(in);

    if (len < 0) {

      throw new CoderException("Invalid encoded SolrDocument length: " + len);

    }



    JavaBinCodec codec = new JavaBinCodec();

    return (T) codec.unmarshal(new BoundedInputStream(in, len));

  }



  @Override

  public TypeDescriptor<T> getEncodedTypeDescriptor() {

    return TypeDescriptor.of(clazz);

  }



  @AutoService(CoderProviderRegistrar.class)

  public static class Provider implements CoderProviderRegistrar {

    @Override

    public List<CoderProvider> getCoderProviders() {

      return Arrays.asList(

          CoderProviders.forCoder(

              TypeDescriptor.of(SolrDocument.class), JavaBinCodecCoder.of(SolrDocument.class)),

          CoderProviders.forCoder(

              TypeDescriptor.of(SolrInputDocument.class),

              JavaBinCodecCoder.of(SolrInputDocument.class)));

    }

  }

}